21458270 has 8 divisors (see below), whose sum is σ = 38624904. Its totient is φ = 8583304.

The previous prime is 21458257. The next prime is 21458279. The reversal of 21458270 is 7285412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21458279) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1072904 + ... + 1072923.

It is an arithmetic number, because the mean of its divisors is an integer number (4828113).

Almost surely, 2^21458270 is an apocalyptic number.

21458270 is a deficient number, since it is larger than the sum of its proper divisors (17166634).

21458270 is a wasteful number, since it uses less digits than its factorization.

21458270 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2145834.

The product of its (nonzero) digits is 4480, while the sum is 29.

The square root of 21458270 is about 4632.3072005211. The cubic root of 21458270 is about 277.8848702922.

The spelling of 21458270 in words is "twenty-one million, four hundred fifty-eight thousand, two hundred seventy".